Our long-term goal is to foster informed reproductive health decisions by young adults with sickle cell disease (SCD) or sickle cell trait (SCT). Unfortunately for many young adults with SCD and SCT pregnancies occur without the opportunity to make well-informed reproductive health decisions, which is related to insufficient or incorrect knowledge of one's or the partner's SCD/SCT status or its genetic transmission. We will determine the long-term 12-, 18- and 24-mo effects on reproductive knowledge and reproductive health behaviors in a two-group design with CHOICES or usual care attention control [eBook] interventions. In this mixed-method application we will complete the efficacy trial, add a new qualitative aim at 24 mos to understand how study participation influenced participants' reproductive behaviors, and with a National Advisory Board (NAB), plan and pilot test the feasibility of a multi-site web-based study in 4 states (CA, TX, NC, CT). Specific aims are to: Aim 1. In 236 young adults (18 to 35 yr) with SCD or SCT, compare usual care and CHOICES boosted (at 12 mos) groups for sustained effects on reproductive health knowledge and reproductive health behaviors (at 12, 18, & 24 mo). At all time points, we hypothesize that knowledge scores and behaviors consistent with the parenting plan will be greater in the CHOICES group than the usual care group. Aim 2. From interviews with 60 of these participants, explore their views about and experience with the aim1 study participation and what influenced their reproductive health behaviors during the study. We will identify conditions under which participants did or did not change their reproductive health behaviors as participants in the control or CHOICES groups, which will be important for interpretation of outcomes and if indicated by qualitative findings to modify the intervention(s). Aim 3. In 100 newly recruited young adults (18 to 35 yr) with SCD or SCT, determine the feasibility of replicating the CHOICES trial as a 24-mo multi-site, community-based study with Internet- and web-based recruitment, delivery, and retention strategies. The recruitment and retention rates and NAB consultation will guide design of procedures for a multi-site national effectiveness study of the CHOICES intervention.